124 



Mycologia 



sissimus, erectiusculus, teres, inarticulatus, glaber, nitidus, inanis, 

 infra nigricans, supra sordide albidus, intus griseus ; ramis paten- 

 tissimis : extremitatibus simplicibus, subulatus," Ehrh., Beitrage 

 zur Naturkunde, 3 : 82-83. 1788. 



Figures : Acharius, Nya Handl. Kongl. Vetenskaps Acad., 

 Stockholm, 22: pi. 4. f. 6a-b. 1801. 



Sowerby, Eng. Bot. 26: pi. 1853. 1808. 



Diagnosis : Thallus caespitose, proximally black, apices pale, 

 branches rigid, nitidous. 



Description : Thallus caespitose, erect or procumbent, 

 filamentous, rigid, branches terete, proximal portions black, 

 apices paler to yellowish ; cortex nitidous, occasionally slightly 

 ruptured with soralia ; primary branches dichotomous, divaricate, 

 flexuous, slender (max. length 11 cm.) ; secondary branches 

 dichotomous, divaricate; fibrils short. Apothecia lateral, rare, 

 small (max. diam. 2-3 mm.), convex, innate-marginate, disk con- 

 colorous, or pale brown. Spores 5-9 X 4~7/*- 



Substrata: On earth, and with mosses over rocks, also on 

 coniferous trees. 



Geographical distribution : Common in the Boreal zone. It 

 has been reported from the following eastern stations : Green- 

 land (Vahl); Labrador (Arnold and others); Newfoundland 

 (Eckfeldt, Arnold) ; Maine (Eckfeldt) ; New Hampshire (Tuck- 

 erman). Dr. Eckfeldt records it from Sussex Co., N. J., but in 

 view of the plant's boreal range this record seems doubtful. The 

 only western station is Alaska (Cummvngs). I have seen the 

 typical plant from Labrador, New Hampshire, and Maine, on 

 the Atlantic coast, and from British Columbia, Alberta, Yukon, 

 and Alaska on the Pacific. 



Observations : This plant is likely to be confused only with 

 nitidula, and particularly, as already noted, with chalybeiformis. 

 From the former it may be distinguished by its bicolored and 

 more slender thallus, and simple apices ; from the latter by its 

 espinulose and esoraliate branches, which are generally largely 

 unicolored. 



Note: Alectoria bicolor Berengeriana Mass. (Anzi, Lich. 

 rariores veneti, etc., Fasc. I, No. 17. 1863) has been reported 

 from Newfoundland by Stizenberger — " Berenger und in New- 

 foundland (im Herbar Hegelschw. als A. diver gens) " 1. c. 127. 



